Analytical model of transient thermal effects in microchip laser crystal

Abstract The proper understanding of cooling temperature and cooldown time for the operation of a subsea system producing hydrocarbons from the reservoir to the host facility is one of the important flow assurance issues for managing heat retention in the production system due to solids formation and their deposition. In this paper, an analytical transient thermal model is developed for determining the cooling temperature and cooldown time for shut-in operations of a subsea pipe-in-pipe production system, transporting waxy crude oil from the reservoir to the host facility. Here, the cooldown time is defined as the time when the fluid temperature approaches the wax appearance temperature before reaching the hydrate formation temperature during any shut-in operations. The analytical model builds upon an inhomogeneous transient method incorporating an internal temperature gradient. The model results are benchmarked against the commercial OLGA simulation results for a few selected deepwater pipe-in-pipe flowline configuration. The model predictions resemble well with OLGA results over a range of conditions. The analytical model could optimize dry insulation and cooldown time requirements efficiently for the assumed PIP flowline configurations and fluid properties under any subsea environments.

Download Full-text

Measurement of Thermal Conductivity of a Flexible Substrate

Volume 8B: Heat Transfer and Thermal Engineering ◽

10.1115/imece2014-39236 ◽

2014 ◽

Author(s):

Vivek Vishwakarma ◽

Ankur Jain

Keyword(s):

Thermal Conductivity ◽

Analytical Model ◽

Flexible Substrate ◽

Thermal Response ◽

Experimental Methodology ◽

Plastic Substrate ◽

The Past ◽

Thin Plastic ◽

Transient Thermal ◽

Transient Thermal Response

A number of past papers have described experimental techniques for measurement of thermal conductivity of substrates and thin films of technological interest. Nearly all substrates measured in the past are rigid. There is a lack of papers that report measurements on a flexible substrate such as thin plastic. The paper presents an experimental methodology to deposit a thin film microheater device on a plastic substrate. This device, comprising a microheater line and a temperature sensor line is used to measure the thermal conductivity of the plastic substrate using the transient thermal response of the plastic substrate to a heating current. An analytical model describing this thermal response is presented. Thermal conductivity of the plastic substrate is determined by comparison of experimental data with the analytical model. Results described in this paper may aid in development of an understanding of thermal transport in flexible substrates.

Download Full-text

An analytical model of SiC MESFETs incorporating trapping and thermal effects

International Semiconductor Device Research Symposium, 2003 ◽

10.1109/isdrs.2003.1272138 ◽

2004 ◽

Author(s):

S.S. Mukhedee ◽

S.S. Islam ◽

R.J. Bowman

Keyword(s):

Analytical Model ◽

Thermal Effects

Download Full-text

Influence of Pump Light Distribution on Thermal Effects within Nd:YAG Microchip Laser

Chinese Journal of Lasers ◽

10.3788/cjl20083505.0643 ◽

2008 ◽

Vol 35 (5) ◽

pp. 643-646 ◽

Cited By ~ 1

Author(s):

史彭 Shi Peng ◽

李金平 Li Jinping ◽

李隆 Li Long ◽

甘安生 Gan Ansheng

Keyword(s):

Thermal Effects ◽

Microchip Laser ◽

Light Distribution ◽

Pump Light

Download Full-text

Transient Thermal Effects in Sedimentary Basins with Normal Faults and Magmatic Sill Intrusions—A Sensitivity Study

Geosciences ◽

10.3390/geosciences9040160 ◽

2019 ◽

Vol 9 (4) ◽

pp. 160 ◽

Cited By ~ 3

Author(s):

Magnhild Sydnes ◽

Willy Fjeldskaar ◽

Ivar Grunnaleite ◽

Ingrid Fjeldskaar Løtveit ◽

Rolf Mjelde

Keyword(s):

Physical Properties ◽

Thermal Effects ◽

Sedimentary Basins ◽

Sensitivity Study ◽

Fault Slip ◽

Structural Development ◽

Potential Source Rock ◽

Magmatic Intrusions ◽

Transient Thermal ◽

Magmatic Sill

Magmatic intrusions affect the basin temperature in their vicinity. Faulting and physical properties of the basin may influence the magnitudes of their thermal effects and the potential source rock maturation. We present results from a sensitivity study of the most important factors affecting the thermal history in structurally complex sedimentary basins with magmatic sill intrusions. These factors are related to faulting, physical properties, and restoration methods: (1) fault displacement, (2) time span of faulting and deposition, (3) fault angle, (4) thermal conductivity and specific heat capacity, (5) basal heat flow and (6) restoration method. All modeling is performed on the same constructed clastic sedimentary profile containing one normal listric fault with one faulting event. Sills are modeled to intrude into either side of the fault zone with a temperature of 1000 °C. The results show that transient thermal effects may last up to several million years after fault slip. Thermal differences up to 40 °C could occur for sills intruding at time of fault slip, to sills intruding 10 million years later. We have shown that omitting the transient thermal effects of structural development in basins with magmatic intrusions may lead to over- or underestimation of the thermal effects of magmatic intrusions and ultimately the estimated maturation.

Download Full-text